(a) Field of the Invention:
The present invention relates to tightening devices, and more particularly, the present invention relates to a tightening device used in securing a bicycle saddle to a seat pillar or securing a bicycle seat pillar to a seat tube.
(b) Description of the Prior Art:
In a bicycle, two retainer plates are connected to the seat pillar by screw bolts and locknuts to hold the bicycle saddle, the seat pillar is adjustably fastened inside a seat tube at the top by a head lock ring. According to the aforesaid structure, it is not convenient to mount or dismount the bicycle saddle or to adjust the position of the seat pillar in the seat tube. Furthermore, a special hand tool shall be used in dismounting the bicycle saddle or adjusting the position of the seat pillar in the seat tube.